TORONTO (AP) — Canadian Prime Minister Mark Carney drew international attention earlier this year by warning that middle powers such as Canada must resist economic coercion. Now President Donald Trump is putting that to the test in a deepening trade war. The United States has imposed 50% duties on about $20 billion worth of Canadian goods. Carney said Canada’s dollar-for-dollar retaliation will begin Sept. 8. Carney’s strategy is to accept economic pain rather than yield to pressure from a larger power. Whether Canada can withstand the cost could shape how Carney is viewed at home and abroad. And it could influence how other U.S. allies respond to Trump.